Endoscopy is a minimally invasive procedure that allows diagnosing conditions inside the gastrointestinal, respiratory or urinary tract, by means of an endoscope which is inserted through a body passageway. Advances in endoscopic medicine have led to the development of therapeutic endoscopy that enables physicians to treat numerous conditions using endoscopic techniques such as the removal of polyps and early tumors.
Endoscopic polypectomy and hot biopsy have become routine electrosurgery procedures for the removal of colonic small or very small polyps in the course of colonoscopy. Other techniques such as endoscopic mucosal resections (EMR) and endoscopic submucosal resections (ESD) allow the removal of larger polyps or early-stage colorectal cancer, thus reducing the need for surgical intervention.
Although these techniques are generally very safe and convenient, in a few cases there are still post-operative complications such as bleeding, transmural thermal injury and perforation.
On the one hand, coagulation syndrome (also known as postpolypectomy electrocoagulation syndrome and transmural burn syndrome) may appear after polypectomy with electrocoagulation and refers to the development of abdominal pain, fever, leukocytosis, and peritoneal inflammation in the absence of frank perforation.
On the other hand, extensive bleeding may cause a surgical procedure to be terminated and might require a transfusion, whereas postoperative perforation is an especially serious adverse event, which generally requires emergency surgery.
Therefore, taking into account the large number of therapeutic endoscopy procedures carried out today, it is imperative trying to avoid such complications regardless of the limited (in percentage) number of cases with complications.
Several approaches for avoiding the post-operative complications after therapeutic endoscopy have been described, including, for example, clipping techniques after colorectal endoscopic resection. However, these procedures require special devices or are quite complex, and besides, the duration of clip persistence remains unknown. Furthermore, polyglycolic acid (PGA) sheets and fibrin glue have been described in the art as endoscopic tissue shields to cover wounds after colorectal endoscopic submucosal dissection (ESD). According to this procedure, several PGA sheets need to be placed on the affected tissue with biopsy forceps. After the whole area is covered, it is sprayed with fibrin glue. However, this method requires a significant amount of time and is thought to be inefficient for covering large mucosal defects.
Niimi K. et al., World J. Gastrointest. Endosc. 2009, 1(1): 61-64, investigated the possible protective effect of a subserosal injection of hyaluronic acid (HA) after endoscopic resection (ER). However, according to the authors' conclusions, the study failed to show any preventative effects of HA on postoperative perforation.
Therefore, there is a need to develop a topical composition, which reduces or avoids post-operative complications after therapeutic endoscopy and contributes to the wound healing.